>>12007649"Adults in early historic times had entities such as household gods and guardian angels, and muses that functioned as imaginary companions to provide comfort, guidance and inspiration for creative work.[3] Eventually, the phenomenon of imaginary companions passed on to children. The era when children began having imaginary friends is unknown, but it is possible the phenomenon appeared in the mid–19th century when childhood was emphasized as an important time to play and imagine." t.wikipedia
imaginary friends is for adults